Centrifugal pump.



R, YATES. CENTRIFUGAL PUMP.

APPLICATION FILED OCT. 2. 1916.

Patented. Got. 29, 918

4: SHEETS-SHEEI 1..

atfozne 1 45 R. L. YATES.

CENTRIFUGAL PUMP.

APPLICATION FILED ocr. 2. 191a.

Patented Oct. 29, 1918.

4 SHEETS-SHEET 2- R. L. YATES. CENTRIFUGALIPUMP- APPLICAHON FILED OCT. 2. 191a.

Patented Oct. 29, 1918.

4 SHEETS R. L. YATES.

CENTRIFUGAL PUMP.

APPLICATION FILED 001.2. 19 16.

Patented Oct. 29, M8.

4 SHEETS-SHEET arena L. YATES, or narro'n'r, OHIO.

' danrnirirear. r.

Specification of Letters Patent. Patented! that. 29, 191%.

Application filed octbbei 2, 1916. Serial no. 123,421.

not individually new, the resulting structure presenting a definite advance in the art in simplicity, strength and efliciency of. operation as well as in ready adaptability to effi- 'cient operation under a wide range of service requirements.

In the preferred embodiment of the invention the casing is a sim le rigid structure divided horizontally on t e axis of the impeller shaft into two main parts. All water passages between stages are formed in the lower or base portion of the casing, so that the joint between the two parts of the casing is a simple one, and the upper part is relatively light and readily removable to expose the shaft and impellers. This construction avoids all external pipe connections between Q'stages uand reduces the number of packing glands'for the shaft to two.

The use of guide vanes and difi'user vanes is avoided, and instead each impeller discharges into a volute chamber so formed as each to receive impellers differing in diameter and in'other details of form; Theimpellers are of the inclo'sed double suction type, and thus according to their diameter project more or less into the annular throat of the volute chamber. The adaptation of any particular type and size of pump to any particular service conditions within its'scope is a mere question of providing it with the proper impellers. The use of double suction impellers has the characteristic advantage of eliminating end thrust, and is made possible in this particular type of pump by the special arrangement of passages devised by me,

A four stage pump embodying the preferred form of the invention is'illustrated in the accompanying drawings, in which Figure 1 is a front elevation of the complete device, certain parts of the housing being broken away to show thearrangement of water passages;

Fig. 2 is a plan view of the same, the casmg of the third stage being shown in sectionpn the line 2-2 of Fig. 8;

Fig. 3 is an enlarged axial section through the first and second stage casings and impellers; Fig. 4 is a side view of an impeller with one of the inclosing shroud platesbroken away to show the vanes;

Fig. 5 is a perspective view of a portion of the impeller shaft and an impeller, the upper half of the impellerbeing broken away to show the internal form;

Fig. 6 is an end elevation of the complete pump looking from the left hand end (with reference to Fig. 1);

Fig. 7 is a transverse section through the impeller shaft, an impeller and its volute chamber-on the line 77 of Fig. 1; and

Fig. 8 is a transverse section throughthe shaft and water passage leading from one lmpeller to the next, taken on the line 88 of Fig 1. r

The lower portion 11 of the casing or housing is box-like in'its general form and is provided with feet or pedestals 12 intended to be bolted to a base plate or other suitable foundation. The housing 11 carries brackets 13 and 14 to support bearing boxes 15 and 16 for the impeller shaft 17 the box 16 inclosing also a thrust bearing of any suitable form (not shown in the drawings) to prevent longitudinal shifting of the impeller shaft 17. The upper portion 18 of the casing or housing is supported on and bolted to the lower portion 11, the plane of thejoint between the two passing through the axis of the impellershaft 17 so that the shaft is freed by the separation of the two portions 11 and 18 of the housing and the removal of the caps of bearing boxes 15 and 16. The particular construction of the bearings isnot a feature of the present invention and hence is not illustrated in detail.

.The impeller shaft 17 is provided with a coupling flange 19 by which it may be connected to any suitable driving means. Near its left end it is provided with an integral collar or flange 20 and near its right end a follower sleeve 21 is threaded on the. shaft'. Between these are assembled a series of bronze impellers 22, 23, 24 and '25 suitably spaced apart by bronze sleeves 26. The impellers are held against turning on shaft 17 by feather keys 27 and are held against axial shifting by the flange 2O follower sleeve 21 bolt-held followers 30 and 31. The uspal: water connections 32 .if-romthe discharge 'slde and sleeves 26. Since the flange 20 and tollower sleeve 21 are outside'the packing boxes 28' "and 29, the shaft is cased in bronze throughout its length within the housing. I

i The packing boxes 28 and 29am suited to the reception of any suitablepackmg (not shown) and are provided withthe ordlnary of adjacent impeller casings tothe packing gland'of each box 28 and 29 areprovided,

;-. valves 33 being used to control such connections. Between the boxes 28 and; 29 and be tween the chambers of adjacent-stages the shaft sleeves f 26 turn in bronze or Babbitt metal bushings'34 mounted in the housing. Similar bushings 35 are provided to receive the eyes of the impellers. .1 I

The impellers are all of the inclosed double suction type, each-consisting of a hub 36 ofthe general form shown-and two annular crown orshroud plates 37. connected to the hub by spiral vanes 38. The inneropenmgs.

of the crown plates 37 which form the eyes of the impellers are reinforced by annular. rims 39 which turn in the bushings 35. The

vanes extend from the eye to the periphery of the impeller, andthe crown plates 37 are dished so as to produce, in conjunction with the hub, water passages whose width de' creases gradually toward the periphery of the impeller. T e form of the spiral vanes and crown plates and the diameter of the impellers are all subject chan e to meet particular service conditions wit out change in the design of any otherparts of the pump,"a

-invention.

of the pump, which as al-- feature of great importance the present The' housing readystated, comprises two separable portions 11' and 18 is soformed' asto provide impeller discharge chambers. 40,41, 42'and 43, one for each of'the' impellers'22, 23, 24

' and 25, and pairs of suction chambers 44, 45, 45

46 and 47' similarly corresponding to the re-' 'spective impellers. The discharge chambers 40' to 43 are substantially fidentica'l'each be- 'ing of the volute or snail shell type. The

annular throats through which the impellers project into the discharge chambers are'all relatively wide to permit the desired intere change of impellers. The' nairs of suction chambers v44 to 47 are also substantiall identical andcommiinicate directly .witht e eyes of the impellers, Since the rims 39 of the impeller eyes'tur n in the bushings 35, a close a seriesof wide-t roate chambers',',each having a pair of suction or inlet passages ,.the outlet of each volute ex- -ceptthe last connecting with the inlet passages of the succeeding volutexchamber; a

branching around the walls of chamber 41 to reach the chambers 45. The discharge passage from chamber 41 passes under port 50 to a port-.51 which is similar to port 50 and which leads to chambers 46. The discharge passage from chamber 42 passes under port 51 t o aport 52 similar to orts 50 and 51, which le'adsto chambers 4 The discharge from chamber 43 passes out through discharge port 53 which has a connecting' flange 54. The four impellers are thus connected in series each discharging to the intake of the next through passages formed wholly in the base portion of the housing and relatively free from sudden changes of direction or cross sectional area. Any number of impellers may besimilarly mounted and connected to produce any de-', sired number of stages. p

In order to prevent eddying ofthe water flowing in passages 48, 50, 51 and 52 the ides 55tare'nrov'ided where the-passages ranch around the dischargev chambers to direct the water to the eye of the next impeller. These a're'best' inshown in Fig. 8.

Having thus describedmy'invention, what 1. The combination of a rotatable shaft; a plurality of inclosed double-suction impellers mounted on said shaft; and asingle longitudinally divided casing inclosing said impellers and formed with a volute discharge chamber'fo'r each impeller, a pair of suction chambers for each impeller, suction and discharge-passages for the first and last impellers. respectively, a and one or more branched connecting passages connecting the discharge and suction chambers of'adbeing formed wholly in one portion ofsaid divided casing. H

. 2. A multi-stage pump, comprising-atwopart shell or casin havin formed within it shaft extending longitudinally through said casing'and having its axisin the dividing 'j'acent'impellers, said connecting passages volute discharge plane, thereof; and a plurality of independ- 'ently replaceable inclosed double suction impellers carried'by said than, one inaeach volute chamber, the suction or inlet passages being formed wholly within one section of the casing.

' 3. The combinationj of ,a rotatable-shaft;

.a plurality of inclos'ed doublesuction im-f pellers mounted on said'shaft; and a single longitudinally divided casing inclosing said .impellers, and formed with a pair of suction chambers for each impeller, wide throated volute discharge chambers each adapted to receive impellers of several diameters, and suitable suction discharge and connecting passages, all said passages being formed in one portion of said divided casing.

4. The combination of a rotatable shaft; a plurality of double-suction impellers mounted on said shaft; and a single divided casing inclosing said impellers and formed with a yolute discharge chamber for each impeller, a pairof suction chambers for each impeller, suction and discharge passages for thefirst and last impellers respectively, and one or more connecting passages each extending from the discharge passage of one impeller longitudinally, and then branching and extending substantially radially inward in the suction chambers of the next impeller.

5. The combination of a rotatable shaft; a plurality of double -suction impellers mounted on said shaft; and a single casing divided longitudinally into abase portion and a cap portion, and formed with a volute discharge chamber for each impeller, a pair of suction chambers for each impeller, said base portion being provided with suction and discharge passages for the first and last impellers respectively, and with one or more connecting passages each extending from the discharge passage of one impeller longitudinally, and then branching and extending substantially radially inward to the suction chambers'of the next impeller.

6. The combination of a rotatable shaft;

a plurality of inclosed double-suction impellers mounted on said shaft; and a single casing divided longitudinally into a base portion-and a cap portion, and formed with a pair of suction chambers for each impeller and a Wide throated volute discharge cham her for each im eller, to permit interchange of impellers di ering in size, said base portion being provided with suction and discharge passages for the first and last impellers respectively, and one or more connecting passages each extending from the discharge passage of one impeller longitudinally, and then branching and extending substantially radially inward to the suction chambers of the next impeller.

In testimony whereof I have signed my name to this specification.

RICHARD L. YATES. 

